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Hey Morpheus fans! In this write-up I’ll take you through
a test day in a fair amount of detail. Most of you only get insight into the
last 20 or so minutes when our Ustream feed goes live. Hopefully you’ll enjoy
this behind the scenes look into all the hard work the team puts in to make
each flight happen.

Overview

As you probably expect test day is a busy day with many
tasks to accomplish to get to ignition. The overall day can be broken up into
several different sections, each of which I’ll go over in more detail below.
The different portions of the day are Safety Brief & Vehicle Rollout,
Pre-Fill Checkout, Propellant Load (Liquid Oxygen and Liquid Methane), Leak
Check, Final Preparation, Flight, and Post Test. A typical test day is about 10
hours from roll-out until Morpheus is back in the hangar. There are two teams
working in tandem to get Morpheus ready for flight, the Pad Crew and Control
Center. The Pad Crew is out at the pad and performs all the physical tasks
needed to get ready for the test; this includes flipping switches and hooking
up hoses. The Control Center operators monitor telemetry and send commands to
Morpheus. (For more details on the various positions see the previous blog
post)

Safety Brief &
Rollout

The test day begins with the entire team meeting at
Morpheus’ hangar, where our PM goes over the plan for the day. The briefing
starts by covering hazard and safety topics applicable for that day’s test,
such as cryogenics, pressure vessels, and laser firings. It’s vitally important
that in a contingency the entire team knows what actions need to be taken.
After the safety brief is covered each discipline reviews changes or items of
note for their subsystem, including giving their concurrence they are ready for
flight. At this point the team is ready to get the test day underway.

The pad crew finalizes Morpheus for transport from the
hangar to the pad area. Morpheus must then be transported from the south end of
the Shuttle Landing Facility (SLF) to the north end. The 3 mile trek takes
about 20 minutes to ensure Morpheus isn’t jostled too much on the ride.

While Morpheus is on the way to the pad, the control team
heads to the SLF air traffic tower where the control center is located. Here
the operators begin configuring their consoles for the test day.

Once Morpheus arrives at the pad it is lifted off the
cart by a crane and placed on launch stands. The three launch stands align with
three load cells on Morpheus that allows the team to monitor the weight and
center of gravity (c.g.) up until the moment of ignition. The launch stands
fall away as Morpheus lifts off. Once on the launch stands, the pad crew then
begins positioning all the ground equipment required to get Morpheus ready for
flight, items such as grounding straps, propellant tankers, and ground power.
When both the pad crew and control center teams are ready, the team powers on
Morpheus’ avionics and moves on to system checkouts.

Pre-Fill Checkout

Prior to loading propellants all of Morpheus’ systems are
checked out. This allows the team to work any issue that may come up before the
cryogenic propellants are onboard. Most of the day Morpheus is powered by a
ground power cart to preserve the onboard flight batteries. Once powered up the
vehicle is precisely leveled on the launch stands using the onboard Inertial
Measurement Unit (IMU). Being level helps ensure that when propellant is loaded
it will settle out evenly between the two tanks.

Once level a process known as ‘Gyrocomping’ is kicked
off. The gyrocomp initializes the accelerometers inside the IMU and must be
performed any time the IMU is powered on. The process is about 3 minutes and
internal to the IMU. During this time the vehicle must be as still as possible
as the gyrocomp uses the sensed rotation of the Earth as part of its process.

After gyrocomp we checkout all the mechanical valves and
actuators to ensure proper function. First, we test out the helium disconnect
mechanism. Helium is used to pressurize the tanks to their flight pressure. A
remote system is needed because the high tank pressures means the pad crew must
be at least 1250 feet away. After a successful disconnect checkout we check all
the other valves (which include vent valves, cooling valves, and engine valves)
on Morpheus. This is a total of 16valves.We
then move on to the actuator check. For this portion we put Morpheus on to
flight batteries to ensure they can handle the power draw required to drive the
actuators simultaneously. There are three elctro-magnetic actuators (EMA’s) on
Morpheus; one drives the throttle and the other two gimbal the engine. With
those checks complete we command each of the four RCS jets valves open and to
spark. Finally, we conclude this portion of checkouts with checking the main
engine spark.

In parallel with the actuator checks we checkout two of
the three ALHAT sensors, the Doppler Lidar and Laser Altimeter. These two
sensors don’t give very useful data until we’re moving, so at this point we are
mainly looking to ensure they booted up properly and that the temperatures are
all nominal. When the actuator and ALHAT checkouts are complete we go back on
to the ground battery cart.

To complete the functional checkouts we test the
remaining ALHAT sensor, the Hazard Detection System (HDS), and the Thrust
Termination System (TTS). The TTS’s main function is to independently shutdown
the main engine should the need arise. The TTS accomplishes this by shutting a
valve on each of the propellant feed systems to the main engine. The TTS also
has a function to stop the HDS laser from firing, thus providing an independent
method to safe that part of the vehicle as well. The HDS system uses a laser
that is not eye safe so extra precautions are taken by the team to ensure
safety. With the HDS system powered, the full functionality of the TTS system
is checked by verifying that it will also stop the HDS laser from firing.The HDS is then pointed at two different
targets to verify pointing accuracy of the system. Precisely pointing the HDS
system is a key requirement for the ALHAT flights.

At the successful conclusion of the functional checkouts
the team prepares to begin loading propellants on to Morpheus.

Propellant Load

At this point the team is ready to load the Liquid Oxygen
(LOX) and Liquid Methane (LCH4) on to Morpheus. Generally, we load LOX first
but can, and have, loaded Methane first. During loading we fill to fairly
precise quantities. Of course we don’t want to run out of propellant during a
flight, but we also don’t want to overfill too much. Any propellant that we
aren’t planning to burn is simply dead weight that we have to carry with us. So
you can see it’s a fine balancing act. This is where it’s very handy to have
Morpheus resting on the three load cells; their weight readings are our best
gas gauge.

Because the propellants are cryogenic, they will continue
to boil off throughout the day and this must be accounted for by the Prop
officer when setting the loading targets. When the propellants are first put
into the tanks they boil off at a very high rate because the tanks are at
ambient air temperature. Once the tanks chill down the boil off rate is very
predictable. To help avoid some uncertainty, after the rapid boil off is
finished we top the tanks back off to the target load. Once both propellants
are loaded the team is really on the clock. If too much propellant is allowed
to boiloff there won’t be enough left to perform the day’s test.

Leak Check

The final checkout that can only be performed once
propellant is on board is a leak check. With cryogenic propellants on board,
seals and fittings can shrink allowing propellant vapors to escape, so a leak
check is performed. Valves are closed to stop the propellants from escaping as
they boil off, and so that pressure can be built up in the tanks. With the pad
crew safely back from the vehicle the tanks are pressurized up to 40 psi with
helium. After a wait period, required personnel are allowed back to Morpheus to
check for leaks and make final torques on the propellant systems. The leak
check generally takes about 35 minutes to complete. For most on the team this
is the final calm before the storm.

When leak check is complete the TTS is checked out one
more time at cryogenic temperatures and then the pressure is released from the
tanks to allow the propellants to cool back down. (The explanation for that
phenomenon is for future blog post.) Morpheus and the team are now ready to
make the final push to flight.

Final Preparation

While the leak check was under way the pad crew was busy
removing any unnecessary equipment and staging it for when the team retreats.
The ground cooling of the avionics is disconnected, Morpheus is switched over
to flight batteries, and the various on-board cameras are turned on. Finally,
the valves are once again closed to allow for pressurization and the crew is
ready to retreat from the pad area. Once the pad crew has safely retreated
pressurization of the tanks begins. Pressurization takes about 20 minutes, and the
flight pressures range from 300-355 psi, depending on the objectives of the
day. As pressures come up we use some of the methane to cool Morpheus’
electronics, and ALHAT is also configured for flight. Once at flight pressure
the helium line is disconnected and retracted to a safe distance.

The team is now ready for the final Go/No-Go poll
conducted by the Test Conductor (TC). With all systems “Go” and final words
from the Flight Manager (FM), the final engine conditioning is performed. The
command to start the onboard ignition sequence is sent. 5…4…3…2…1…

Flight

If you’ve seen the video then I think this section speaks
for itself. (A future blog will detail what Morpheus and ALHAT are doing during
the flight)

Post Test

Once Morpheus is safely on the ground at the landing pad
the control team executes the necessary commands to safe the vehicle systems
prior to allowing the pad crew to head down range. This means venting leftover
pressure, making sure there’s no fires on the vehicle, and that the laser has
stopped firing.

Once down range, the pad crew works to put Morpheus on
stands, so the control team can get weight readings as propellant offload
occurs. If need be, the pad crew will also hook up ground cooling and
power.Propellant off-load happens one
commodity at a time to get an accurate reading of how much remained on board.
This information helps to refine the engine model used to predict performance.
Once offload is complete, Morpheus is rolled back to the hangar where the
vehicle methane tanks are inerted for safety, post-flight inspections are
completed, and high-rate data is offloaded in preparation for the next flight.

Test days are obviously a busy time for the Morpheus
team. This blog is to give all of you some insight into who the players are. In
a future blog we’ll bring you a narrative of a test day.

Who makes up the team and what their roles & responsibility are on the day of a test.

Flight Manager (FM) – The Flight Manager has overall responsibility of the test. This is the position that represents project management, usually either the Project or Deputy Project manager. The FM coordinates any external interfaces needed on test day. They monitor the day’s activities and give the final Go/No-Go for the test.

Test Conductor (TC) – This position is in charge of all the test day operations. The TC focuses on overall vehicle and crew safety, while integrating operations between the various control disciplines and the pad crew. TC also performs all the voice communications between the control center and pad crew. The position can be likened to the Flight Director in the Shuttle or Station mission control room.

Morpheus Control Center at Kennedy Space Center during a Free Flight Test Day

Operator – Assists TC in the day’s operations, and helps ensure all steps are completed as required in the test procedures. The Operator sends all commands to the vehicle leading up to and including the start of the ignition sequence. The Operator also develops the day of flight procedures used by the team.

Range Safety Officer (RSO) – Staffed by a member of the
test safety group from JSC, the RSO has ultimate responsibility that Morpheus
stays inside the range boundaries defined at KSC. Should the RSO feel the
vehicle poses a threat to any personnel they have the ability to terminate the
flight via the independent Thrust Termination System (TTS). The RSO has the
authority to terminate the test independent of the operations team at any point
they deem necessary.

Test Area Manager (TAM) – The TAM is Morpheus’ liaison to
KSC. On test days the TAM clears the SLF air space, and coordinates with the
NASA Air Traffic Control tower. The TAM also coordinates other KSC operations,
such as crane riggers and truck operators for the cryogenic tankers.

Guidance, Navigation, & Control (GNC) – The GNC
console is in charge of designing the day’s trajectory as well as the sensors
such as GPS and Inertial Measurement Units (IMU) that keep the vehicle headed
in the right direction. The trajectory is developed several days ahead of time
so that many simulations can verify the correct parameters are set on the day
of flight. On the day of flight the GNC makes final tweaks to the plan to
account for test day variability like the actual prop load and the winds of the
day. The GNC console must also monitor the GNC sensors for anomalous behavior
and to ensure they are properly initialized prior to flight.

Propulsion (Prop) – The Prop console is responsible for
all components related to the propulsion systems of Morpheus. This includes
propellant tanks, main engine, Reaction Control System (RCS), and feed systems.
Based on the trajectory design of the day the Prop console will calculate the
propellant load of Liquid Oxygen (LOX) and Liquid Methane. Their calculations
have to include main engine run-time, boil-off, and reserve. During the flight
Prop monitors the main engine and RCS thrusters for correct performance.

Avionics and Power Systems (APS) – APS monitors the
flight computer and power systems. Morpheus has flight battery system that must
be verified prior to flight. There are a number of electrical systems that must
be monitored throughout the day to ensure a successful flight.

ALHAT – When the Autonomous Laser Hazardous Avoidance
Technology (ALHAT) package is installed on the vehicle, this position monitors
the health of the three ALHAT sensors (Doppler Lidar, Laser Altimeter, and
Hazard Detection System)

Ground Data Systems (GDS) – The control center has
multiple workstations the operators use for command and telemetry and these are
maintained by the GDS. GDS is staffed by the Flight Software (FSW) group and
are in charge of both the ground systems software and the on-board flight
software.

Morpheus Comm – These folks are responsible for the
command and telemetry radios that relay Morpheus data back to the control
center, along with the infrastructure that goes along with it. They also set up
many of the cameras that are used for situational awareness inside the control
center, as well as streamed out to our live audience.

Pad Crew: There are a number of Pad Crew that prepare the
vehicle for test flight.

PAD 1 – PAD 1 coordinates all pad activity. Throughout
the day the vehicle is put through functional checks, filled with propellants,
leak checked, and put into final preparations. There are a number of personnel
that help accomplish these tasks, including crane riggers, cryo operators, and
other Morpheus personnel.

A note from Jenny Devolites, SE&I Lead for Morpheus, after a successful Free Flight Campaign in December...

As everyone who follows Morpheus knows, our first
Morpheus “Campaign Zero” free flight test campaign at Kennedy Space Center in
2012 ended with a spectacular vehicle crash, after 26 successful static hot
fire and tethered tests. Shortly after the crash, our Project Manager, Jon
Olansen, gathered the sad but resolute team at the KSC hazard field landing pad
and reiterated, “this is why we test.” We keep the dream, we learn from our
failures, and we try again. NASA management, all the way to the top, understood
the risks, and immediately turned us around to rebuild and fly again, because
they understand the value of what we are trying to achieve. They can do this,
because we are a low cost and lean project with an incredibly dedicated and
competent team – a team who wants to build rockets and spacecraft and do
whatever they can to help further human spaceflight and exploration.

Last week we had our first successful free flight of the
“Bravo” vehicle. The flight was impressively on target with regard to the planned
trajectory. All of the things we worried so much about – because of the Alpha
vehicle crash and all of the testing since then – turned out to not be problems
on that beautiful flight test day. There was definitely something redeeming for
the team and the Agency -- to show that we could do this.

This past weekend, a bunch of the Morpheus team members
went to KSC’s new “Atlantis” space shuttle orbiter visitor’s center. The
exhibit is phenomenal, and found many of us with tears in our eyes as we revisited
that amazing engineering endeavor coming to a close. One part of the historical
film struck me – that the engineers who conceived of the space shuttle set out
to make it a reusable spacecraft. Many rocket engines and spacecraft are
single-use. Our little vertical test bed – our lander – is also designed to be
reusable. But we don’t have thousands upon thousands of team members or a
budget like that – we are a small project with less than 50 people (and that’s
padding the number).

So just doing one successful free flight would be a
career achievement – but two in one week is a tribute to the hard work and
efforts by a team that has become like family. Today’s free flight went higher,
and further, and faster – and it was 82 seconds of picture-perfect flying.

Last year after the crash, I remember vividly walking to
the building next to our KSC vehicle hangar and seeing the Alpha vehicle
wreckage for the first time up close. The crash itself had happened so fast
that there was barely time to comprehend what happened. But there was the
wreck, our wonderful creation, smashed and burned.

Today I waited outside in the sunshine (we’ve been lucky
on weather this week here in Florida compared to much of the country) for the
Bravo vehicle to be driven back to the hangar. I watched it roll in and
marveled at the gift I have been given to be an aerospace engineer on a project
such as this one. After today’s flight test we will spend a couple of days
inspecting the systems and putting away all of the ground support equipment to
get it ready for Campaign One in January, where we will fly increasingly
challenging flight trajectories with our prototype lander vehicle.

The roar of a 5,000lb rocket engine has returned to the Johnson Space Center. The Morpheus team has completed the build-up of our “Bravo” vehicle, conducted numerous integrated tests, and has now stepped into our flight test program. We are picking up where we left off – in fact we never stopped working. We have completed our first major milestone in conducting a 50-second static hot fire of the main engine in the vehicle, including simultaneous demonstration of thrust vector control (TVC) and integrated methane reaction control system (RCS) jet firings. Thrust vector control is used to balance and fly the vehicle, while the RCS jets are used to keep the vehicle pointed in the correct direction. We will step into dynamic tethered flights soon, in preparation for our return to KSC this summer.

The knowledge and insight we gained over the 27 test firings of the previous vehicle are fully incorporated into the testing we’re beginning now. Although a hardware failure led to the loss of the original vehicle last August, the failure and our internal investigation gave us valuable insight into areas that needed improvement. The vehicle may look largely the same as the previous version, but there are numerous changes that have been incorporated. We have now implemented 70 different upgrades to the vehicle and ground systems to both address potential contributors to the test failure, and also to improve operability and maintainability.

The Morpheus team has been hard at work preparing for this year’s series of tests and building the new Morpheus 1.5B and 1.5C vehicles. We have been busy assembling the vehicle structures, wiring in all of our sensors, running integrated tests, continuing engine firings at Stennis Space Center, and more.

Hard at Work

The Morpheus and ALHAT teams are now a combined team, which enables a more integrated series of tests as we prepare for future flight tests. One of these integrated tests took place at Kennedy Space Center in December. We used a Langley Research Center Huey helicopter as a stand-in for Morpheus. We mounted the ALHAT sensors under the belly of the helicopter pointed in the direction of the helicopter motion. Other components such as sensor electronics, Morpheus flight computer, real-time communications equipment and support hardware were placed in the passenger/cargo area. This allowed both onboard and ground support teams to monitor progress in real-time. The helicopter was flown repeatedly on Morpheus-type trajectories towards the hazard field.

On Thursday we made our second free flight attempt with the Morpheus prototype vehicle. As you can see in the video below, shortly after liftoff we experienced a hardware failure and lost the vehicle. The root cause is still under investigation, but what we do know is that at the start of ascent we lost data from the Inertial Measurement Unit (IMU) that supplies navigation updates to the flight computer. Without this measurement the vehicle is blind and does not know which way it is pointing or accelerating. Since this data is needed to maintain stable flight, the vehicle could not determine which way was up and began to tumble and impacted the ground about 50 feet from the launch site. No one was injured, no property was damaged besides the vehicle and we have been able to recover significant data, which will give us greater insight into the source of the problem.

We have said it before and will continue to say, this is why we test. We have already learned a lot from this test and will continue to learn as we recover data and evaluate the hardware. No test article should be too precious to lose. A spare vehicle was planned from the start and is just a few months away from completion. The basic development approach is to quickly build, test and redesign the hardware to achieve many design cycles and maturity before building flight articles.

The Morpheus team successfully flew our first tether test at Kennedy Space Center on Friday August 3rd. The objectives for this flight, along with the dry and wet runs earlier in the week, were to verify all systems were in good working order after shipping from Johnson Space Center in July and to allow the new KSC support team an opportunity to move through flight procedures.

After looking over the data over the weekend and coming together for a Test Readiness Review, our Project Manager, Jon Olansen, approved our first ever free flight for August 7th. This will be the first time we will fly the vehicle without a crane attached. The crane was used in previous tests as a safety mechanism to allow each subsystem to safely tune their individual systems for a smooth stable flight.